This section is from the book "Cyclopedia Of Architecture, Carpentry, And Building", by James C. et al. Also available from Amazon: Cyclopedia Of Architecture, Carpentry And Building.
The first set of holes from the left-hand end in the web is for the connection of an 8-in. beam framed to this beam. Note that 5 5/16 in., the spacing horizontally of these holes, and 2 1/2 in., the spacing vertically, are the measurements in the outstanding legs of the standard connection for an 8-in. I-beam.
The single hole at the right-hand end is for a standard anchor rod. This measurement of 2 in. from the end is a customary measurement on such anchor holes, although some specification may call for something different.
In the flange near the left hand is shown a group of holes; these are for the connection of a channel which runs over the top of beam. As these holes are not symmetrical with regard to the axis used in locating the group, it is necessary to space each set with regard to their axis. These holes are spaced symmetrically with respect to the web of beam, and the distance between them is the standard gauge for punching the flange of an 8-in. beam. Where holes come in a flange these standard gauges should always be followed unless there are special reasons for not doing so.
In the drawing, the plan of the bottom flange is given, although there are no holes in it. Where printed forms ready for filling in measurements and details are used, this would appear and it is added here for clearness. In actual details, however, it should not be drawn if it involves extra work and if there is no punching or cuts to be shown.
Fig. 197 shows a channel detail which is similar to Fig. 196 except that it is coped. In such cases, always specify the size and weight of beam to which it is coped and give the relation of the tops or bottoms, as for instance, "cope to a 12 in., 31 1/2-lb. I-beam flush on bottom", or "cope to a 12-in., 31 1/2-lb. I-beam as shown". In case the beams do not cope flush on top or bottom, the outline of the beam to which it copes should be shown in red in the sketch, and the relations of flanges clearly indicated.
Below the sketch in beam details, is always given the specification of size and weight of beam or channel and the overall length, the number of pieces wanted and the mark to be put on them. This specification is used by the mill in entering the order for its rolling list and it is important that it agrees with the detailed measurements in the sketch. Also if the beam is cut on a bevel the extreme length
LA SALLE STATION, L. S. & M. S. AND C, R. I. & P. RAILROADS, CHICAGO.
View showing method of setting steel by hand. Note that the lifted column will rest on top of a column Just above the floor line, seen to the right of the place where the lifted column rests on the ground. The bottom of the column rests between cover-plates, to which the column is riveted. The projection shown near top of lifted of beam required to give the specified bevel should be given. Fig. 198 shows a beam girder bearing a shelf angle for the support of wind joists, or a terra cotta arch of different depth from the beam. This requires an additional line of dimensions, giving the rivet spacing and the length and position of angles. The maximum rivet pitch of six inches is generally used. Where this angle interferes with connection holes or separator bolts, as in Fig. 198, it has to be cut, and in such cases the rivet pitch must be figured out to agree with the measurements fixing the connection holes or separators.
LA SALLE STATION, L. S. & M. S. AND C. R. I. & P. RAILROADS, CHICAGO, ILL.
Frost & Granger, Architects; E. C. & R. M. Shankland, Engineers.
Steel Frame Showing Method of Attaching Angle-Iron Shelf to Spandrel Beam. This Occurs at
They are Fastened to the Floor Beams at Top and Bottom.
At the top or bottom of a sheet, such general directions as apply to the work as a whole are given, as "Rivets, 3/4 in. diam. except noted". "Open holes 13/16 in. diam., except as noted". "Paint, one coat Superior graphite".
The student should carefully study all the dimensions in connection with the cuts, and should thoroughly understand these and the problems before starting on the subject of detailing from a plan. Note at each side of a beam sketch, are figures preceded by a plus or minus sign. These measurements denote the distance from the end of the beam in the sketch to the center of the beam or column or other member to which it connects, or the distance from face of the wall to end of the beam. These figures are not necessary for the complete detailing of the beam, but they are of great assistance in checking the drawings, as they show just how much is to be added to or substracted from the measurements on the setting plan to give the length of piece as detailed.
1. Practice making freehand letters of the style shown on the details, both capitals and small letters. Make the letters in each word of uniform size, also practice making letters of different sizes. This is important as it is often necessary on shop drawings to put a note on a part of the drawing where space is very limited, and the writing must be small. Make a copy of the alphabet (capitals and small letters) and a copy of the numerals; also print the following in three sizes:
"All bearing plates to be faced."
One size to have a height of 3/16 in. for the small letters, another size 1/8 in. high, and the third size 1/16 in. high.
2. Make a shop drawing of a 6-in. I-beam, 6 ft. long, with two holes for 5/8-in. rivets in top flange at each end, and 1 1/2 in. from the ends. Also make holes for 3/4-in. rivets spaced 6 in. apart in the middle of the web for the full length. The end holes should be 3 in. from the end of the beam.
In this example, the only work specified is the punching of the rivet holes, and therefore, as no other work is required, the shop drawing will consist only of the outlines of the beam, with the rivet holes located on the same, and the spacing of the rivets shown by dimension lines, as indicated in Fig. 196.
3. Given a 20-in., 65-lb. I-beam 22 ft long, framed into a 20-in., 80-lb. I beam. The 20-in., 65-lb. I-beam has a 15-in., 42-lb. I-beam framed into each side every 5 ft. 6 in. with its top flush with the 20-in. I-beam. If the reaction of each 15-in. I-beam is 7 tons, state the number of 3/4-in. rivets required for the connections of the 20-in., 65-lb. beam and for the connection of the 15-in. beam, using 9,000 pounds for shear and 18,000 pounds for bearing.
4. Make a shop detail of the 20-in., 65-lb. beam in the above problem, using standard connections.